ANTENNA APPARATUS INCLUDING FREQUENCY SEPARATOR HAVING WIDE BAND TRANSMISSION OR REFLECTION CHARACTERISTICS

摘要

The antenna apparatus comprises frequency separator means having a plurality of frequency-selective reflecting surface members (FSRS 12) for separating electromagnetic waves, and two electromagnetic horns (13, 14) for feeding the electromagnetic waves to the surface members (12) at an arbitrary angle. Each of the surface members (12) comprises a lattice with a periodic pattern of conductive material and inherent resonance frequency. Said inherent resonance frequency is substantially the same in each of the surface members (12), and the lattice is capable of serving as an inductive-capacitive circuit element at specific frequency region lower than the inherent resonance frequency. The lattice exhibits substantially equal inductance and capacitance with respect to the electromagnetic waves when made obliquely incident in the TE and TM modes. The surface members (12) have an interactive resonance at a frequency lying within the specific frequency region. …This antenna apparatus with the frequency separator is relieved of the performance deterioration resulting from the oblique incidence of electromagnetic waves on FSRSs where the FSRSs are regarded as the resonance elements of LCs.